1. Field of the Invention
The present invention relates to enzymatic methods and compositions for removing excess dye from dyed or printed materials, such as textiles, and to enzymatic methods and compositions for dyeing such materials.
2. Description of Related Art
A major problem involved with the use of disperse dyes for dyeing or printing of textile materials made from polyester fibers, polyester-containing blends and other fibers and fiber blends, is the tendency of these dyes to aggregate and deposit on the surface of the dyed or printed material. As a result of this residual dye formation, washfastness and wetfastness of the textile material is negatively affected, that is, the unintentional staining of other materials resulting from dyes that migrate from a dyed or printed fabric to another fabric during washing or wetting, often seen when white laundry becomes colored during washing. In addition to washfastness and wetfastness, residual dyes can also undermine the brightness of a shade as well as affect sublimation and crockfastness results of the dyed or printed material.
In order to improve the quality of textile materials, textile manufactures can select dyes that migrate as little as possible during washing. Alternatively, or in addition, textile manufactures can remove excess disperse dyes from newly prepared textiles in post-clearing or after-clearing processes. Traditional after-clearing processes involve repeated water rinses and/or chemical treatments, such as, reduction clearing processes, in which a dyed or printed fiber is treated with a strong alkaline reducing bath, usually containing sodium hydrosulfite and caustic soda. Reduction clearing processes, however, require high temperatures and alkaline conditions, which may damage the fabric and are expensive and time consuming to carry out.
Improvements in removing excess dye from dyed or printed materials, such as textile materials, are therefore desired.